SECOND AMENDMENT

SECOND  AMENDMENT,  dated as of  December  29, 1998 (this  "Amendment"),  to the
Second  Amended and  Restated  Credit  Agreement,  dated as of June 6, 1997,  as
amended  and  restated  through  September  14, 1998 and as amended by the First
Amendment  dated as of November  19, 1998 (the  "Credit  Agreement"),  among Key
Energy  Group,  Inc.  (now  known as Key  Energy  Services,  Inc.),  a  Maryland
corporation  (the  "Borrower"),  the several  Lenders  from time to time parties
thereto,  PNC Bank,  National  Association  ("PNC"),  as  Administrative  Agent,
Norwest Bank Texas, N.A., as Collateral Agent and PNC Capital Markets,  Inc., as
Arranger.

The parties hereto hereby agree as follows:

Defined Terms.  Unless otherwise defined herein,  terms which are defined in the
Credit Agreement and used herein as defined terms are so used as so defined.

Amendments  to  Subsection  1.1  (Definitions).  Subsection  1.1 of  the  Credit
Agreement is hereby amended as follows:

A.  by  deleting  the  definition  of   "Consolidated   Interest   Expense"  and
substituting in lieu thereof the following:

"'Consolidated  Interest  Expense':  for  any  period,  total  interest  expense
(including that  attributable to Capital Lease  Obligations),  both expensed and
capitalized,  of the borrower and its  Subsidiaries for such period with respect
to all outstanding Indebtedness of the Borrower and its Subsidiaries (including,
without limitation,  all commissions,  discounts and other fees and charges owed
with  respect to letters of credit and  bankers'  acceptance  financing  and net
costs under Interest Rate Protection Agreements to the extent such net costs are
allocable to such period in accordance  with GAAP,  and excluding fees owed with
respect to the Existing Credit Agreement,  this Agreement, the Put Facility, the
Senior Subordinated  Notes, the Convertible  Subordinated  Debentures,  the 1997
Convertible  Subordinated  Notes  or the  refinancing  of the  1997  Convertible
Subordinated Notes and the imputed interest  attributable to Senior Subordinated
Notes that are original issue discount notes) determined on a consolidated basis
in  accordance  with  GAAP,  net of  interest  income of the  Borrowers  and its
Subsidiaries for such period  (determined on a consolidated  basis in accordance
with GAAP).";

B. by deleting clause (a) of the definition of "Consolidated Leverage Ratio" and
substituting in lieu thereof the following new clause (a):

"(a)  Consolidated  Total Debt on such  date,  less the sum of (i) the amount of
cash and Cash  Equivalents in excess of $5,000,000  held by the Borrower and its
Subsidiaries on such date and (ii) the aggregate principal amount of Convertible
Subordinated  Debentures and 1997 Convertible  Subordinated Notes outstanding on
such date to";

C. by deleting the definition of "Minimum Equity Event" and substituting in lieu
thereof the following:

"'Minimum Equity Event':  an aggregate  increase of at least  $75,000,000 in the
Consolidated  Net Worth of the Borrower and its  Subsidiaries  occasioned by (i)
the receipt by the  Borrower of Net Cash  Proceeds  from the issuance of Capital
Stock of the Borrower after the Closing Date,  (ii) one or more issuances by the
Borrower of its Capital Stock in connection  with the acquisition of one or more
Persons  or the assets of one or more  Persons,  (iii) the sale of Odessa or its
assets,  (iv)  the  exchange  or  other  refinancing  of  the  1997  Convertible
Subordinated Notes or (v) any combination thereof; provided, in the case of each
of the  foregoing  clauses (i) through (v),  that no Default or Event of Default
shall have occurred and be continuing; and provided,  further, that in the event
a Minimum Equity Event would  otherwise occur as the result of any of the events
referred to in the  foregoing  clauses (ii) through (v), a Minimum  Equity Event
shall  not be  deemed to occur  unless  and until the ratio of (x)  Consolidated
Total Debt to (y) the sum of Consolidated Total Debt plus Consolidated Net Worth
of the Borrower and its Subsidiaries is equal to or less than 75%.";

D. by deleting the definition of "Permitted  Acquisitions"  and  substituting in
lieu thereof the following:

"'Permitted Acquisitions':  the acquisition by the Borrower and its Subsidiaries
of (a) rigs and other well service equipment, (b) well service companies and (c)
oil and gas  properties  and related  equipment,  provided that (i) after giving
effect  to  such  acquisitions  and  any  borrowings   hereunder  in  connection
therewith,  (x) the  Consolidated  Leverage Ratio shall not be more than 2.75 to
1.00 and (y) the sum of (1) the Borrower's cash and Cash Equivalents on hand and
(2) the aggregate Available Revolving Commitments shall be at least $20,000,000,
or (ii) after giving effect to such acquisition the Consolidated  Leverage Ratio
is not  increased  and such  acquisition  is funded  solely with the  Borrower's
Capital Stock.";

E. by deleting from the  definitions of "Applicable  Margin" and "Commitment Fee
Rate" each reference to the  "Consolidated  Leverage Ratio" and  substituting in
lieu thereof a reference to the "Pricing Ratio"; and

F. by adding in the appropriate alphabetical order the following new definition:

"'Pricing  Ratio': on the date of any  determination  thereof,  the ratio of (a)
Consolidated  Total  Debt on such  date,  less  the  amount  of  cash  and  Cash
Equivalents in excess of $5,000,000 held by the Borrower and its Subsidiaries on
such date to (b)  Consolidated  EBITDA of the Borrower and its  Subsidiaries for
the four full fiscal quarters ending on such date; provided that for purposes of
calculating  Consolidated  EBITDA of the Borrower and its  Subsidiaries  for any
period of four full  fiscal  quarters,  the  Consolidated  EBITDA of any  Person
acquired by the Borrower or its Subsidiaries which upon such acquisition becomes
a  Consolidated  Subsidiary  or is  merged  into the  Borrower  or a  Subsidiary
(including,  without limitation, Dawson and its Subsidiaries) during such period
shall be  included  on a pro  forma  basis for such  period of four full  fiscal
quarters  (assuming the consummation of each such acquisition and the incurrence
or assumption of any Indebtedness in connection  therewith occurred on the first
day of such  period of four full fiscal  quarters  and  assuming  only such cost
reductions as are related to such  acquisition  and are  realizable on or before
the date of  calculation)  if the  consolidated  balance  sheet of such acquired
Person and its  consolidated  Subsidiaries as at the end of the period preceding
the acquisition of such Person and the related consolidated statements of income
and  stockholders'  equity  and of cash  flows  for such  period  (i) have  been
previously provided to the Administrative  Agent and the Lenders and (ii) either
(A) have been  reported on without a  qualification  arising out of the scope of
the audit (other than a "going concern" or like  qualification  or exception) by
independent  certified public accountants of nationally  recognized  standing or
(B) have been found acceptable by the Administrative Agent."

Amendment to Subsection 7.1 (Financial Condition  Covenants).  Subsection 7.1 is
hereby amended as follows:

G. by deleting Subsection 7.1(a) and substituting in lieu thereof the following:

7.1 Financial Condition Covenants.

(a) Consolidated  Leverage Ratio.  Permit the Consolidated  Leverage Ratio as of
any date set forth below to exceed the ratio set forth below opposite such date:

- ------------------------------------- ------------------------------
                                                     Consolidated
Date                                 Leverage Ratio
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
December 31, 1998                              5.90 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
March 31, 1999                                 5.90 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
June 30, 1999                                  5.90 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
September 30, 1999                             5.90 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
December 31, 1999                              5.75 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
March 31, 2000                                 5.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
June 30,2000                                   4.50 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
September 30, 2000                             4.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
December 31, 2000                              3.75 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
March 31, 2001                                 3.50 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
June 30, 2001                                  3.25 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
September 30, 2001                             3.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
December 31, 2001                              3.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
March 31, 2002                                 3.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
June 30, 2002                                  3.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
September 30, 2002                             3.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
December 31, 2002                              3.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
March 31, 2003                                 3.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
June 30, 2003                                  3.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
September 30, 2003                             3.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
December 31, 2003                              3.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
March 31, 2004                                 3.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
June 30, 2004                                  3.00 to 1.00
- ------------------------------------- ------------------------------
- ------------------------------------- ------------------------------
September 30, 2004                             3.00 to 1.00;
- ------------------------------------- ------------------------------

H. by deleting Subsection 7.1(b) and substituting in lieu thereof the following:

(b)  Consolidated  Interest  Coverage Ratio.  Permit the Consolidated  Interest
Coverage  Ratio  for any  period  of four  consecutive  fiscal  quarters  of the
Borrower  ending  as of any date set  forth  below to be less than the ratio set
forth below opposite such date:

- -------------------------------- ------------------------------------
                                              Consolidated
Date                                           Interest
                                            Coverage Ratio
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
December 31, 1998                         1.50 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
March 31, 1999                            1.50 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
June 30, 1999                             1.50 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
September 30, 1999                        1.40 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
December 31, 1999                         1.50 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
March 31, 2000                            1.75 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
June 30, 2000                             1.75 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
September 30, 2000                        2.00 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
December 31, 2000                         2.25 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
March 31, 2001                            2.50 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
June 30, 2001                             2.50 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
September 30, 2001                        2.75 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
December 31, 2001                         3.00 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
March 31, 2002                            3.25 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
June 30, 2002                             3.50 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
September 30, 2002                        3.75 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
December 31, 2002                         4.00 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
March 31, 2003                            4.00 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
June 30, 2003                             4.00 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
September 30, 2003                        4.00 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
December 31, 2003                         4.00 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
March 31, 2004                            4.00 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
June 30, 2004                             4.00 to 1.00
- -------------------------------- ------------------------------------
- -------------------------------- ------------------------------------
September 30, 2004                        4.00 to 1.00
- -------------------------------- ------------------------------------

; provided, that for the purposes of determing the ratio described above for the
fiscal  quarters of the Borrower  ending  December 31, 1998,  March 31, 1999 and
June 30, 1999,  Consolidated  Interest  Expense for the relevant period shall be
deemed to equal  Consolidated  Interest Expense for such fiscal quarter (and, in
the case of the latter two such  determinations  each  previous  fiscal  quarter
commencing after September 30, 1998) multiplied by 4, 2 and 4/3, respectively.;

I. by deleting Subsection 7.1(c) and substituting in lieu thereof the following:

(c)  Consolidated  Senior Leverage  Ratio.  (i) Permit the  Consolidated  Senior
Leverage  Ratio as of any date set  forth  below to  exceed  the ratio set forth
below opposite such date:

- ---------------------------------------- ----------------------------------

                                           Consolidated
                                               Senior
Date                                       Leverage Ratio
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
December 31, 1998                                 4.50 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
March 31, 1999                                    4.50 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
June 30, 1999                                     4.50 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
September 30, 1999                                4.50 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
December 31, 1999                                 4.25 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
March 31, 2000                                    3.75 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
June 30, 2000                                     3.25 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
September 30, 2000                                2.75 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
December 31, 2000                                 2.50 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
March 31, 2001                                    2.25 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
June 30, 2001                                     2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
September 30, 2001                                2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
December 31, 2001                                 2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
March 31, 2002                                    2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
June 30, 2002                                     2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
September 30, 2002                                2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
December 31, 2002                                 2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
March 31, 2003                                    2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
June 30, 2003                                     2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
September 30, 2003                                2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
December 31, 2003                                 2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
March 31, 2004                                    2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
June 30, 2004                                     2.00 to 1.00
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
September 30, 2004                                2.00 to 1.00";
- ---------------------------------------- ----------------------------------
 
J. by deleting Subsection 7.1(d) and substituting in lieu thereof the following:

(d)  Consolidated Net Worth.  Permit the Consolidated Net Worth of the Borrower
and its  Subsidiaries to be less than the sum of (i) the difference  between (x)
$135,000,000  minus (y) the amount (in the aggregate  for the following  clauses
(A),  (B)  and  (C),  taken  together,   not  to  exceed   $15,000,000)  of  (A)
non-recurring  transaction expenses incurred in connection with the consummation
of the  Acquisition,  (B) related  financing and  restructuring  charges and (C)
writeoff of goodwill and licensing agreements, plus (ii) 75% of Consolidated Net
Income of the Borrower and its  Subsidiaries  (to the extent a positive  number)
for each fiscal quarter  completed  after the Closing Date  commencing  with the
fiscal quarter ending December 31, 1998, plus (iii) 75% of the Net Cash Proceeds
of any  offerings or  issuances  of Capital  Stock of the Borrower or any of its
Subsidiaries  after  the  Closing  Date,  plus (iv) 75% of the  increase  in the
Consolidated Net Worth of the Borrower and its  Subsidiaries  resulting from any
conversion of the 1997 Convertible  Subordinated Notes or any future convertible
indebtedness of the Borrower and its Subsidiaries.; and

K. by adding a new Subsection 7.1(e) as follows:

(e) Consolidated EBITDA.  Permit the Consolidated EBITDA of the Borrower and its
Subsidiaries for any period of four consecutive  fiscal quarters of the Borrower
ending on any date set forth  below to be less than the amount  set forth  below
opposite such date:

- ---------------------------------------- ----------------------------------
                                                 Consolidated
Date                                               EBITDA
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
December 31, 1998                                 $140,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
March 31, 1999                                     115,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
June 30, 1999                                      100,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
September 30, 1999                                  95,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
December 31, 1999                                  100,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
March 31, 2000                                     115,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
June 30, 2000                                     125,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
September 30, 2000                                135,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
December 31, 2000                                 140,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
March 31, 2001                                    145,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
June 30, 2001                                     150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
September 30, 2001                                150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
December 31, 2001                                 150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
March 31, 2002                                    150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
June 30, 2002                                     150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
September 30, 2002                                150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
December 31, 2002                                 150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
March 31, 2003                                    150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
June 30, 2003                                     150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
September 30, 2003                                150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
December 31, 2003                                 150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
March 31, 2004                                    150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
June 30, 2004                                     150,000,000
- ---------------------------------------- ----------------------------------
- ---------------------------------------- ----------------------------------
September 30, 2004                                150,000,000
- ---------------------------------------- ----------------------------------
 
; provided that for purposes of calculating  Consolidated EBITDA of the Borrower
and its Subsidiaries  for any such period of four  consecutive  fiscal quarters,
the  Consolidated  EBITDA  of  any  Person  acquired  by  the  Borrower  or  its
Subsidiaries which upon such acquisition becomes a Consolidated Subsidiary or is
merged into the Borrower or a Subsidiary (including,  without limitation, Dawson
and its Subsidiaries)  during such period shall be included on a pro forma basis
for such period of four full fiscal quarters  (assuming the consummation of each
such  acquisition  and the  incurrence  or  assumption  of any  Indebtedness  in
connection  therewith  occurred  on the  first  day of such  period of four full
fiscal  quarters and assuming  only such cost  reductions as are related to such
acquisition  and are  realizable  on or before the date of  calculation)  if the
consolidated  balance  sheet  of  such  acquired  Person  and  its  consolidated
Subsidiaries  as at the end of the  period  preceding  the  acquisition  of such
Person and the  related  consolidated  statements  of income  and  stockholders'
equity and of cash flows for such  period (i) have been  previously  provided to
the Administrative  Agent and the Lenders and (ii) either (A) have been reported
on without a  qualification  arising out of the scope of the audit (other than a
"going  concern" or like  qualification  or exception) by independent  certified
public  accountants  of  nationally  recognized  standing or (B) have been found
acceptable by the Administrative Agent.

Amendment to Subsection  7.2  (Limitation  on  Indebtedness).  Subsection 7.2 is
hereby amended by deleting  clause (b)(ii) and  substituting in lieu thereof the
following:
(ii)  Senior  Subordinated  Notes (x) in an  aggregate  principal  amount not to
exceed  $300,000,000  (plus, in the case of Senior  Subordinated  Notes that are
original issue discount  notes,  an amount equal to the amount of such discount,
provided that the imputed  interest  represented  thereby shall be in compliance
with clause (iii) of the definition of the term "Senior  Subordinated Notes" and
with the following clause (y)) and (y) in the event that the aggregate principal
amount of Senior Subordinated Notes exceeds $150,000,000,  bearing interest at a
rate per annum not in excess of 13%;  provided that (A) the proceeds thereof are
used to prepay the Put Facility or prepay Term Loans as provided in Section 2.10
(and Guarantee Obligations of the Borrower's Subsidiaries in connection with the
foregoing  as  contemplated  hereby)  and (B) in the  event  that the  aggregate
principal amount of Senior  Subordinated  Notes equals or exceeds  $125,000,000,
the Interim Loan Agreement is amended (in form and substance satisfactory to the
Administrative  Agent) so that the  covenants,  events of default  and  remedies
therein conform,  in all material respects,  to those in the Senior Subordinated
Notes, and.

Amendment to Subsection  7.3  (Limitation  on Liens).  Subsection  7.3 is hereby
amended  by  deleting  subsection  (g)  and  substituting  in lieu  thereof  the
following:

(g) Liens created pursuant to the Security  Documents  (including Liens securing
the Put  Facility  until the Merger Date and Liens  securing  the Dawson  9-3/8%
Notes on and after the  Merger  Date)  and Liens on Cash  Equivalents  which are
acquired  in  connection  with  the  defeasance  permitted  by  Section  7.10 of
$1,406,000 of the Dawson 9-3/8% Notes;.

Amendment to Subsection 7.8 (Limitation on Capital Expenditures). Subsection 7.8
is hereby  amended by deleting in its entirety  the table set forth  therein and
substituting in lieu thereof the following table:

Fiscal Year Amount
1999 $30,000,000
2000 $30,000,000
2001 $35,000,000
2002 $45,000,000
2003 $55,000,000
2004 $65,000,000".

Amendment to Annexes I and II to Credit Agreement  (Pricing Grids A and B). Each
of Annex I and Annex II to the Credit  Agreement  is hereby  amended by deleting
therefrom each reference to the  "Consolidated  Leverage Ratio" and substituting
in lieu of each such reference a reference to the "Pricing Ratio".

Conditions to  Effectiveness  of this  Amendment.  This  Amendment  shall become
effective  as of the date (the  "Effective  Date")  that (a) the  Administrative
Agent shall have received (i) this  Amendment,  executed and delivered by a duly
authorized  officer  of  the  Borrower  and  the  Lenders,   (ii)  the  attached
Acknowledgment and Consent,  executed and delivered by a duly authorized officer
of each of the signatories  thereto,  (iii) such other  corporate  documents and
resolutions as the Administrative Agent may request and (iv) payment of all fees
required  to be paid by the  Borrower,  as agreed upon by the  Borrower  and the
Administrative  Agent,  and  (b) an  amendment  to the  Interim  Loan  Agreement
(providing for modifications that conform,  as applicable,  to the modifications
of the Credit  Agreement  set forth in this  Amendment),  in form and  substance
satisfactory  to the  Administrative  Agent,  shall  have  become  effective  in
accordance with the terms thereof.

                                 Miscellaneous.

L.  Representations and Warranties.  The Borrower represents and warrants to the
Administrative Agent and the Lenders that as of the Effective Date, after giving
effect to this  Amendment,  no Default or Event of Default has  occurred  and is
continuing,  and the  representations  and warranties made by the Borrower in or
pursuant to the Credit  Agreement or any Loan  Documents are true and correct in
all material  respects on and as of the  Effective  Date as if made on such date
(except to the extent that any such  representations  and  warranties  expressly
relate to an earlier date,  in which case such  representations  and  warranties
were true and correct in all material respects on and as of such earlier date).

M.  Continuing  Effect  of  the  Credit  Agreement.  This  Amendment  shall  not
constitute  an amendment or waiver of or consent to any  provision of the Credit
Agreement  not  expressly  referred to herein and shall not be  construed  as an
amendment,  waiver or  consent to any  action on the part of the  borrower  that
would require an  amendment,  waiver or consent to any action on the part of the
Borrower that would require an amendment, waiver or consent of the Agents or the
Lenders  except as expressly  stated  herein.  Except as expressly  consented to
hereby,  the  provisions  of the Credit  Agreement  are and shall remain in full
force and effect.

N. Fees and Expenses. The Borrower agrees to pay or reimburse the Administrative
Agent on demand for all its reasonable out-of-pocket costs and expenses incurred
in connection with the  preparation and execution of this Amendment,  including,
without  limitation,  the reasonable  fees and  disbursements  of counsel to the
Administrative Agent.

O.  Counterparts.  This Amendment may be executed in any number of  counterparts
(including by telecopy) by the parties hereto,  each of which  counterparts when
so executed  shall be an original,  but all  counterparts  taken  together shall
constitute one and the same instrument.

P. GOVERNING  LAW. THIS AMENDMENT AND THE RIGHTS AND  OBLIGATIONS OF THE PARTIES
UNDER THIS  AMENDMENT  SHALL BE GOVERNED BY, AND  CONSTRUED AND  INTERPRETED  IN
ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.


IN WITNESS  WHEREOF,  the parties  hereto have caused this  Amendment to be duly
executed and  delivered by their proper and duly  authorized  officers as of the
day and year first above written.

KEY ENERGY SERVICES, INC. (formerly known as Key
Energy Group, Inc.)


By: /s/ Stephen E. McGregor
Title: Executive Vice President and Chief
       Financial Officer 


PNC BANK, NATIONAL ASSOCIATION, as Administrative
Agent and as a Lender


By: /s/ Thomas A. Majeski
Title: Vice President 



NORWEST BANK TEXAS, N.A.


By: /s/ Dale S. Gravelle 
Title: Vice President 



BANK POLSKA KASA OPIEKI S.A., PEKAO S.A. GROUP, NEW
YORK BRANCH


By: /s/ Hussein E. El-Tawil
Title: Vice President 



BANK LEUMI, USA


By: /s/ Gloria Bucher
Title:  First Vice President                         



BOEING CAPITAL CORPORATION


By: /s/ James C. Hammersmith 
Title: Senior Documentation Officer 



THE CIT GROUP/EQUIPMENT FINANCING, INC.


By: /s/ Eric M. Moore 
Title: Assistant Vice President 



KZH HIGHLAND-2 LLC


By: /s/ Virginia Conway 
Title:  Authorized Agent                             


KZH PAMCO LLC


By: /s/ Virginia Conway
Title: Authorized Agent 



PAMCO CAYMAN LTD.

By: Highland Capital Management, L.P., as
     Collateral Manager


By: /s/ James Dandero 
Title: President 

ML CLO XX PILGRIM AMERICA (CAYMAN) LTD.

By: Pilgrim Investments, Inc. as its
     Investment Manager


By: /s/ Jason T. Groom 
Title:  Assistant Vice President                     


PILGRIM PRIME RATE TRUST

By: Pilgrim Investments, Inc., as its
     Investment Manager


By: /s/ Jason T. Groom
Title:  Assistant Vice President                     


MERRILL LYNCH PRIME RATE PORTFOLIO

By: Merrill Lynch Asset Management, L.P., as
     Investment Advisor


By: /s/ Gilles Marchand
Title:  Authorized Signatory                         

MERRILL SENIOR FLOATING RATE FUND, INC.



By: /s/ Gilles Marchand
Title: Authorized Signatory 



              
                           ACKNOWLEDGMENT AND CONSENT

Each of the undersigned corporations,  as a guarantor under that certain Amended
and Restated  Master  Guarantee and  Collateral  Agreement,  dated as of June 6,
1997,  as  amended  and  restated  through   September  14,  1998  (as  amended,
supplemented or otherwise modified from time to time, the "Guarantee"),  made by
each of such  corporations  in favor of the Collateral  Agent,  ackowledges  the
foregoing  amendment  and confirms and agrees that the  Guarantee  is, and shall
continue to be, in full force and effect and is hereby ratified and confirmed in
all  respects and the  guarantee  and all of the  Collateral  (as defined in the
Guarantee)  do,  and  shall  continue  to,  secure  the  payment  of  all of the
Obligations  (as  defined  in  the  Guarantee)  pursuant  to  the  terms  of the
Guarantee.  Capitalized  terms  not  otherwise  defined  herein  shall  have the
meanings  assigned to them in the Credit Agreement  referred to in the Amendment
to which this Acknowledgment and Consent is attached.


                                YALE E. KEY, INC.
                            KEY ENERGY DRILLING, INC.
                             WELLTECH EASTERN, INC.
                         ODESSA EXPLORATION INCORPORATED
                        KALKASKA OILFIELD SERVICES, INC.
                            WELL-CO OIL SERVICE, INC.
                           PATRICK WELL SERVICE, INC.
                            MOSLEY WELL SERVICE, INC.
                           RAM OIL WELL SERVICE, INC.
                           ROWLAND TRUCKING CO., INC.
                         LANDMARK FISHING & RENTAL, INC.
                            DUNBAR WELL SERVICE, INC.
                           FRONTIER WELL SERVICE, INC.
                            KEY ROCKY MOUNTAIN, INC.
                             KEY FOUR CORNERS, INC.
                                JETER SERVICE CO.
                            JETER WELL SERVICE, INC.
                           JETER TRANSPORTATION, INC.
                        INDUSTRIAL OILFIELD SUPPLY, INC.
                           BROOKS WELL SERVICING, INC.
                              UPDIKE BROTHERS, INC.
                        J.W. GIBSON WELL SERVICE COMPANY
                      KEY ENERGY SERVICES-SOUTH TEXAS, INC.
                     WATSON OILFIELD SERVICE & SUPPLY, INC.
                          WELLTECH MID-CONTINENT, INC.


                       DAWSON PRODUCTION MANAGEMENT, INC.
                       DAWSON PRODUCTION ACQUISITION CORP.
                         DAWSON PRODUCTION TAYLOR, INC.
                      KEY ENERGY SERVICES-CALIFORNIA, INC.


By: /s/ Stephen E. McGregor 
Name: Stephen E. McGregor 
Title: Vice President of each of the foregoing 
        companies 


DAWSON PRODUCTION PARTNERS, L.P.


By: DAWSON PRODUCTION MANAGEMENT, INC., Its
     sole general partner,


By:      /s/ Stephen E. McGregor                              
Name: Stephen E. McGregor
Title:  Vice President